The present invention relates to an optical pick-up apparatus to record and reproduce the information onto the optical information recording medium having a plurality of information recording layers, in layer-like, and a light converging optical system of the optical pick-up apparatus, and optical information recording and reproducing method, and particularly to an optical pick-up apparatus to record or reproduce the information onto a laminated plurality of information recording layers, by using a luminous flux whose image side numerical aperture is not smaller than 1.0, using an evanescent light, a light converging optical system of the optical pick-up apparatus, and optical information recording and reproducing method.
Recently, accompanied by putting to practical use of the short wavelength red semiconductor laser, a DVD (digital versatile disk) whose dimension is almost the same as the CD (compact disk) which is the conventional optical disk, that is, optical information recording medium, and whose capacity is largely increased and which is the high density optical disk, is developed, and put into the market, however, it is forecasted that, in near future, the higher density next generation optical disk is also comes into the market. In the optical system of the optical information recording and reproducing apparatus using such the optical disk as the medium, in order to intend to highly increase the density of the recording signal, or to reproduce the high density recording signal, it is required that the spot diameter which is light converged onto the recording medium through the light converging optical system is reduced. For such the requirement, as a solution means the optical element using the principle of near field is proposed. The high NA of such the optical element is attained by using the evanescent light which is leaked from a solid immersion lens opposite to the information recording surface, and for example, it is written in Japanese Tokkai No. 2000-99990.
However, when the information is recorded or reproduced to the optical information recording medium by using the evanescent light, because the evanescent light has the characteristic which rapidly attenuates corresponding to the distance, it is necessary that the information recording surface is formed on the surface of the optical information recording medium. However, a fact that the information recording surface is formed on the surface of the optical information recording medium, is that the protective layer can not be provided on the information recording surface. Accordingly, when it is used only in the hermetically shielded space, such the optical information recording medium can be used, however, for the removable optical disk such as the CD or DVD whose presupposition is that the user exchanges it by his hand, it is difficult that the information is recorded or reproduced by using the evanescent light.
Further, in order to intend to record or reproduce the high density information, the multi-layer type optical information recording medium in which the information recording layer is laminated, is also developed. When the recording or reproducing of the information is conducted onto such the optical information recording medium, it is a problem how makes the information recording light including the evanescent light form an image onto each of information recording layers.